A Southern Alps and Northern Pyrenees Holocene record of snowmelt-induced flood events and clastic layers associated with negative NAO phases inWestern Europe
International audience The origin of both extreme flood events in Lake Ledro (southern Italian Alps) and coarse sandy layers in twodisconnected lakes from the Bassies valley (Lakes Majeur and Sigriou, northern Pyrenees) have been relatedto the impact of snowmelt processes enhancing erosion of mounta...
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Language: | English |
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HAL CCSD
2014
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Online Access: | https://hal.science/hal-01790135 |
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ftunivtoulouse2:oai:HAL:hal-01790135v1 |
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record_format |
openpolar |
institution |
Open Polar |
collection |
Université Toulouse 2 - Jean Jaurès: HAL |
op_collection_id |
ftunivtoulouse2 |
language |
English |
topic |
[SDE.ES]Environmental Sciences/Environment and Society [SDE.MCG]Environmental Sciences/Global Changes [SDU.ENVI]Sciences of the Universe [physics]/Continental interfaces environment |
spellingShingle |
[SDE.ES]Environmental Sciences/Environment and Society [SDE.MCG]Environmental Sciences/Global Changes [SDU.ENVI]Sciences of the Universe [physics]/Continental interfaces environment Simonneau, Anaëlle Chapron, Emmanuel Galop, Didier A Southern Alps and Northern Pyrenees Holocene record of snowmelt-induced flood events and clastic layers associated with negative NAO phases inWestern Europe |
topic_facet |
[SDE.ES]Environmental Sciences/Environment and Society [SDE.MCG]Environmental Sciences/Global Changes [SDU.ENVI]Sciences of the Universe [physics]/Continental interfaces environment |
description |
International audience The origin of both extreme flood events in Lake Ledro (southern Italian Alps) and coarse sandy layers in twodisconnected lakes from the Bassies valley (Lakes Majeur and Sigriou, northern Pyrenees) have been relatedto the impact of snowmelt processes enhancing erosion of mountainous drainage basins (1, 2) throughout theHolocene. Because of increasing human impact on catchment erosion processes since the mid-Holocene in thesewestern European mountain ranges, this study compares these well-dated lacustrine sequences in order to furtherdocument the influence of westerlies and of the North Atlantic Oscillation on clastic supply in contrasted lakebasins. The integrative approaches performed on each site allow us to show that organic and minerogenic markers,such as non-pollen microsfossils, Rock-Eval pyrolysis or X-ray microfluorescence, are powerful tools to identifyclastic sediment source areas. At Ledro, we therefore demonstrated that over the Late Holocene snowmelt-inducedflood events essentially remobilized high altitude pasture areas whereas afterwards the flood events affectedformer forested areas from lower altitude1. In the Pyrenees, the southern slopes of lakes Majeur and Sigriouare characterized by two narrow canyons whose drainage basins are disconnected, relatively small and limitedto the high altitude part of the valley of Bassiès. Our results demonstrated that the mid–late Holocene periodwas regularly interrupted by coarse sandy layers affecting both lakes Majeur and Sigriou and reflecting the highsensitivity of the two active canyons to intense rainfall or snowmelt periods2. While extreme flood deposits inLake Ledro during the Bronze Age period may result from the combination of both climate and human activities,contemporaneous extreme flood events in Ledro and coarse sandy layers in the Bassiès lakes, dated to AD 1710,AD1530, AD1360, AD940, AD570 and 1850, 1050, 1410, 1850, 2690, 4190, 4800 cal BP, testify of regionalhydrological events synchronous with European climatic ... |
author2 |
Institut des Sciences de la Terre d'Orléans - UMR7327 (ISTO) Bureau de Recherches Géologiques et Minières (BRGM)-Observatoire des Sciences de l'Univers en région Centre (OSUC) Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris Université Paris Sciences et Lettres (PSL)-Université Paris Sciences et Lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris Université Paris Sciences et Lettres (PSL)-Université Paris Sciences et Lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS) Géographie de l'environnement (GEODE) Université Toulouse - Jean Jaurès (UT2J) Université de Toulouse (UT)-Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS) Geophysical Research Abstracts ANR-11-LABX-0010,DRIIHM / IRDHEI,Dispositif de recherche interdisciplinaire sur les Interactions Hommes-Milieux(2011) |
format |
Conference Object |
author |
Simonneau, Anaëlle Chapron, Emmanuel Galop, Didier |
author_facet |
Simonneau, Anaëlle Chapron, Emmanuel Galop, Didier |
author_sort |
Simonneau, Anaëlle |
title |
A Southern Alps and Northern Pyrenees Holocene record of snowmelt-induced flood events and clastic layers associated with negative NAO phases inWestern Europe |
title_short |
A Southern Alps and Northern Pyrenees Holocene record of snowmelt-induced flood events and clastic layers associated with negative NAO phases inWestern Europe |
title_full |
A Southern Alps and Northern Pyrenees Holocene record of snowmelt-induced flood events and clastic layers associated with negative NAO phases inWestern Europe |
title_fullStr |
A Southern Alps and Northern Pyrenees Holocene record of snowmelt-induced flood events and clastic layers associated with negative NAO phases inWestern Europe |
title_full_unstemmed |
A Southern Alps and Northern Pyrenees Holocene record of snowmelt-induced flood events and clastic layers associated with negative NAO phases inWestern Europe |
title_sort |
southern alps and northern pyrenees holocene record of snowmelt-induced flood events and clastic layers associated with negative nao phases inwestern europe |
publisher |
HAL CCSD |
publishDate |
2014 |
url |
https://hal.science/hal-01790135 |
op_coverage |
Vienne, Austria |
genre |
North Atlantic North Atlantic oscillation |
genre_facet |
North Atlantic North Atlantic oscillation |
op_source |
EGU General Assembly 27/04-02/05/2014 https://hal.science/hal-01790135 EGU General Assembly 27/04-02/05/2014, Geophysical Research Abstracts, 2014, Vienne, Austria |
op_relation |
hal-01790135 https://hal.science/hal-01790135 |
_version_ |
1810464554215276544 |
spelling |
ftunivtoulouse2:oai:HAL:hal-01790135v1 2024-09-15T18:24:14+00:00 A Southern Alps and Northern Pyrenees Holocene record of snowmelt-induced flood events and clastic layers associated with negative NAO phases inWestern Europe Simonneau, Anaëlle Chapron, Emmanuel Galop, Didier Institut des Sciences de la Terre d'Orléans - UMR7327 (ISTO) Bureau de Recherches Géologiques et Minières (BRGM)-Observatoire des Sciences de l'Univers en région Centre (OSUC) Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris Université Paris Sciences et Lettres (PSL)-Université Paris Sciences et Lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris Université Paris Sciences et Lettres (PSL)-Université Paris Sciences et Lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS) Géographie de l'environnement (GEODE) Université Toulouse - Jean Jaurès (UT2J) Université de Toulouse (UT)-Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS) Geophysical Research Abstracts ANR-11-LABX-0010,DRIIHM / IRDHEI,Dispositif de recherche interdisciplinaire sur les Interactions Hommes-Milieux(2011) Vienne, Austria 2014 https://hal.science/hal-01790135 en eng HAL CCSD hal-01790135 https://hal.science/hal-01790135 EGU General Assembly 27/04-02/05/2014 https://hal.science/hal-01790135 EGU General Assembly 27/04-02/05/2014, Geophysical Research Abstracts, 2014, Vienne, Austria [SDE.ES]Environmental Sciences/Environment and Society [SDE.MCG]Environmental Sciences/Global Changes [SDU.ENVI]Sciences of the Universe [physics]/Continental interfaces environment info:eu-repo/semantics/conferenceObject Conference papers 2014 ftunivtoulouse2 2024-06-24T23:37:51Z International audience The origin of both extreme flood events in Lake Ledro (southern Italian Alps) and coarse sandy layers in twodisconnected lakes from the Bassies valley (Lakes Majeur and Sigriou, northern Pyrenees) have been relatedto the impact of snowmelt processes enhancing erosion of mountainous drainage basins (1, 2) throughout theHolocene. Because of increasing human impact on catchment erosion processes since the mid-Holocene in thesewestern European mountain ranges, this study compares these well-dated lacustrine sequences in order to furtherdocument the influence of westerlies and of the North Atlantic Oscillation on clastic supply in contrasted lakebasins. The integrative approaches performed on each site allow us to show that organic and minerogenic markers,such as non-pollen microsfossils, Rock-Eval pyrolysis or X-ray microfluorescence, are powerful tools to identifyclastic sediment source areas. At Ledro, we therefore demonstrated that over the Late Holocene snowmelt-inducedflood events essentially remobilized high altitude pasture areas whereas afterwards the flood events affectedformer forested areas from lower altitude1. In the Pyrenees, the southern slopes of lakes Majeur and Sigriouare characterized by two narrow canyons whose drainage basins are disconnected, relatively small and limitedto the high altitude part of the valley of Bassiès. Our results demonstrated that the mid–late Holocene periodwas regularly interrupted by coarse sandy layers affecting both lakes Majeur and Sigriou and reflecting the highsensitivity of the two active canyons to intense rainfall or snowmelt periods2. While extreme flood deposits inLake Ledro during the Bronze Age period may result from the combination of both climate and human activities,contemporaneous extreme flood events in Ledro and coarse sandy layers in the Bassiès lakes, dated to AD 1710,AD1530, AD1360, AD940, AD570 and 1850, 1050, 1410, 1850, 2690, 4190, 4800 cal BP, testify of regionalhydrological events synchronous with European climatic ... Conference Object North Atlantic North Atlantic oscillation Université Toulouse 2 - Jean Jaurès: HAL |